The rear 60, if you want to narrow it, just get some Set 20 (bearing size) bearing cups and have them welded on to the desired width. Then buy 35 spline semifloating shafts of appropriate length. If you want to keep the FF, and you have the small spindles, you can whack those off and weld on FF 14 bolt spindles, which accept 35 spline shafts. Then use the 14 bolt hubs.